def sum(a,b):
    return a+b

class Test_sum():
    def test_01(self):
        print(sum(1, 3))
    def test_02(self):
        print(sum(1, 3))
    def test_03(self):
        print(sum(1, 3))
    def test_04(self):
        print(sum(1, 3))